CONJOINED FOR LIFE, THE HENSEL TWINS ARE A MEDICAL MYSTERY AND A LESSON IN COOPERATION FOR US ALL

IT'S PLAY PERIOD IN Connie Stahlke's kindergarten room. Abigail and Brittany Hensel are at the Play-Doh table, when a visitor asks, How much is 10 plus 10? Britty starts counting on her fingers. Abby helpfully lays down her hand on the table. They count fingers and toes with all the accuracy their six-year-old minds can muster. "Nineteen," they conclude. Then the clearly ancient guest asks, "Guess how old I am." Britty can't resist the chance to tease: "900,000!" she shrieks. The sisters dissolve into giggles. They reach up and slap a celebratory high five.